Hmm..... back when I played a lot, this was my quest as well.
An important question and factor is tension. I was a high tension guy when I played with multis and such and I tried playing polys in the mid to upper 50's - but that didn't go well for my arm. Frankly, a good poly doesn't NEED to be at a super high tension.
Anyway, back to your point. Cyclone 16 was my go to string for a while and it worked OK for me though it was hard on my arm. If I had dropped it to the low 40's for tension, maybe that would have worked. To be clear, this is plain Cyclone, not Cyclone Tour, which is/was on my list of strings to try. Cyclone Tour is supposedly softer feeling, though not quite as low powered as plain Cyclone - again, from what I've heard. There's a guy on here who is a big advocate of Cyclone Tour, maybe he'll chime in.
Other ones I tried:
Ytex Quadro Twist 16L @ 53 lbs - nice, good control, nice on the arm, not as crisp feeling as Cyclone, but much more comfortable. Good spin.
Isospeed Pyramid 16 @ 50 lbs - seemed pretty stiff when stringing, but didn't feel that way when playing. Very low powered. Decent spin.
Isospeed Cream 16L @ 50 lbs - good control, medium power for a poly, decent feel. Pretty comfy, but not as much as Quadro Twist. Round poly with ok spin. Has an odd feel, a little, but a good string for the price.
Prince Vortex 16 @ 49 lbs - Kind of just an Ok string. Good control, but not better than the others. Decent spin, but not better than Pyramid, Quadro Twist, or Cyclone. Not bad on the arm, but not super nice, either. Meh.
Tourna Big Hitter Black 7 17 @ 48 lbs - My new favorite of the above. Has nice bite on the ball, but really nice feel for a poly. Very nice on the arm. Not the lowest powered poly, but not exactly a ton of pop, either. Good spin, getting close to Cyclone.